June 19, 2013

Post: How to Monitor MySQL with Percona's Nagios Plugins

February 22, 2012 By 11 Comments

…full LVM snapshots. LVM backup strategies can fail to delete snapshots after finishing, sometimes due to…to delete one of MySQL‘s log or data files from disk. The database server will continue to…to open or close tables can…to a query. The pmp-check-mysql-status is also very flexible and can be used to…

Filed Under: Insight for DBAs, MySQL

Post: How to recover deleted rows from an InnoDB Tablespace

February 20, 2012 By 4 Comments

…to delete the records of the employee 10008 from the table “salaries”. After the “accidental” deletion of rows you should stop MySQL…to_date); Query OK, 3 rows affected (0.01 sec) Records: 3 Deleted: 0 Skipped: 0 Warnings: 0 mysql…

Filed Under: Insight for DBAs, MySQL

Post: Identifying the load with the help of pt-query-digest and Percona Server

December 29, 2011 By 3 Comments

…tables: 0 Tmp_table_sizes: 0 # InnoDB_trx_id: F00 # QC_Hit: No Full_scan: Yes Full_join: No Tmp_table: No Tmp_table….00 0.00 DELETE poller_output # 20 …Tables” section lists the queries that you can use to gather more data about the underlying tables involved and the query execution plan used by MySQL…

Filed Under: Insight for DBAs, MySQL

Post: Fighting MySQL Replication Lag

September 22, 2008 By 7 Comments

… Fetching data you’re planning to update/delete and having multiple queries to delete it (see example below) This brings us to yet another rule for… need to run UPDATE Example: UPDATE posts SET spam=1 WHERE body LIKE “%cheap rolex%”; This query will perform full table scan in MySQL 5…

Filed Under: Insight for DBAs Tagged With: ,

Comment: Database problems in MySQL/PHP Applications

August 11, 2006 By 13 Comments

…MySQL. Good design will help dictate how many tables are required in order to get the job done. To…to fix it. Most > applications I have to fix have number of indexing missing which > requires queries to do full table…

Filed Under: Insight for Developers Tagged With: , ,

Post: MySQL Query Cache

July 27, 2006 By 70 Comments

…Query Cache – meaning cache where execution plans are cached. MySQL Query Cache is not. It does not cache the plan but full…queries Application objects might need several queries to compose so it is efficient to cache whole objects rather than individual queries. No control on invalidation Table…

Filed Under: Insight for DBAs Tagged With:

Post: Full Text Search Webinar Questions Followup

August 24, 2012 By 5 Comments

…to the MySQL queries would make them even slower, I’m sure. Indeed, the result set of 20 rows from SphinxQL queries…to Solr and Sphinx, do indexes stay up to date with changes (inserts, updates and deletes…

Filed Under: Events and Announcements, Insight for Developers, MySQL

Post: InnoDB Full-text Search in MySQL 5.6 (part 1)

February 26, 2013 By 1 Comment

…InnoDB full-text search in MySQL 5.6 (part 1) in MySQL 5.6 is syntactically identical to MyISAM full-text…mysql> delete from dir_test_innodb LIMIT 200000; Query OK, 200000 rows affected (8.65 sec) mysql> optimize table dir_test_innodb; +———————-+———-+———-+———-+ | Table…

Filed Under: Insight for DBAs, Insight for Developers, MySQL Tagged With: , , , , ,

Post: Ultimate MySQL variable and status reference list

January 8, 2011 By 4 Comments

…to the amazing MySQL manual, especially the option and variable reference table. But just as frequently, I want to…

Filed Under: Insight for DBAs, MySQL

Post: Using Flexviews - part two, change data capture

March 25, 2011 By 26 Comments

…table to the list of tables to changelog. It does this by adding an entry to the `flexviews`.`mvlogs` metadata table, and it creates the changelog table…delete data in a second transaction: mysql> delete from test.demo where c1=1; Query…

Filed Under: Insight for DBAs, Insight for Developers, MySQL
« Older Posts